Self-adjusting pipe wrench



Aug. 13, 1940- R. E. I ILLEBERG SELF-ADJUSTING PIPE WRENCH Filed Nov. 23, 1938 ,Z'ZVeWZZ Patented Aug. 13, 1940 unirse smrss SELF-ADJUSTING PIPE WRENCH Ralph E. Lilleberg, Chicago, Ill., assigner to The Nye Tool and Machine Works, Chicago, Ill., a

corporation of Illinois Application November 23, 1938, Serial No. 241,930

3 Claims.

This invention relates to wrenches and more particularly to improvements in self-adjusting pipe wrenches, although certain features thereof may be employed with equal advantages for other purposes.

It contemplates more especially the provision of an improved pipe wrench constructed from stamping to minimize the production costs and to increase the longevity thereof.

Numerous types of wrenches have heretofore been designed, and renement has been eiTected in self-adjusting pipe wrenches which have long been in use and on the market. These wrenches so far as known are produced from forgings which render their costs comparatively high. Further, the initial die cost and depreciation thereof for forgings is a substantial item of expense so that wrenches prepared from forgings have not been conducive to availing wrenches to the purchasing public at popular prices. Then, too, the production of wrenches from forgings renders it necessary to subject all of the parts to substantially the same heat treatment. This is not desirable in that the jaws of the wrench require a certain heat treatment while the other parts such as yokes supporting the jaw should be subjected to different heat treatments to render such more ductile rather than brittle which is a characteristic usually possessed by wrench jaws. This emphasizes the importance of having detachable jaws in connection with the wrench structure and to render the entire tool capable of production from stampings. Thisv has been accomplished by the teachings of the present invention. v

One object of the present invention is to simplify the construction and improve the operating characteristics cik hand tools such as wrenches.

Another object is to provide self-adjusting pipe wrenches with detachable confronting jaws so as to render such reversible and aiiord the proper heat treatment thereof without impairing any other part of the wrench structure or assembly.

Still another object is to provide jaw plates stamped or otherwise shaped so that a plurality thereof will constitute a detachable element.

A further object is to provide a self-adjusting pipe wrench. assembly from stampings to provide an inexpensive and durable tool having detachable jaw plates to permit each element thereof to receive the proper heat treatment as well as increase the longevity of use thereof.

A still further object is to provide a'pipe Wrench having detachable jaw plates mounted on parts thereof to constitute stampings so as to enable the production of a durable and inexpensive pipe or nut turning tool. l

Still a further object is to 'providea combina- 5 tion of stampings which can be assembled into a unitary self-adjusting pipe wrench structure which is durable, dependable and aiiords'jaw replacement to the end of rendering improved service at a minimum cost. 10

Other objects and advantages will appear from the following description of an illustrative embodiment of the present invention.

In the drawing:

Figure 1 is a front edge view in elevation of a wrench embodying teachings of the present invention, part of the handle being shown in section to clarify the showing.

Figure 2 is a side view in elevation of the wrench shown in Figure 1.

Figure 3 is a sectional View taken substantially along line III-III of Figure 2.

Figure 4 is a sectional view taken substantially along lineIV-IV of Figure 2.

lFigure 5 is a top plan View of the wrench shown in Figures 1 and 2.

Figure 6 is a side View of a single upper detachable plate.

The structure selected for illustration comj prises a pair of confronting' handle members Il) 3,0 and II which are stamped from heavy sheets of steel to provide bowed elongated handle portions terminating in reduced Shanks I2 and I3 which are correspondingly shaped to dene convexoconcavo complemental elements intended for assembly into a cylindrically enclosed handle IIi-II and integral reduced Shanks I2-I3. The open lower lends of the handle portions IIJ- II are enclosed by a seamless tubular handle grip I4 which is pressed over the handle portions lll-II for connection thereto by means of a pin I 5 extendmg diametrically therethrough. The handle grip I4 is stamped, rolled, or otherwise formed from metallic sheet material to present an enclosed lower end I6 with knurled rings I'I thereon to increase the manual gripping'eiect thereon.

Aligned apertures I 8 are stamped proximate to the enclosed end IB of the handle grip I4 so as to be in diametrical registry :for receiving a turn- 50 ing rod therethrough or to facilitate the mounting of the wrench structure on a nail or other support as commercial practice may dictate. Another aperture I9 is provided in the end of the handle grip member I4 to enable the removal of foreign substances and avoid their collection therein. It will be observed that the convexoconcavo handle portions lll-H are substantially cylindrical in configuration while the reduced shanks |2|3 are elliptical in form in order to present a larger cross-section in the direction of the application of force, thereby increasing the capacity of the handle shanks |2|3 which terminate proximate to their upper end in spaced and laterally offset portions 20 and 2| that have upper straight horizontal edges 22 and 23. The spaced handle shank extensions 20-2l receive a pair of arcuate yoke plates 24 and 25 therebetween, the yoke plates 24-25 being stamped from heavy sheet material to terminate upwardly in spaced laterally offset extensions 26-21 that are designed to receive a pair of upper hardened jaw plates 28--29 therebetween.

Another pair of hardened jaw plates 3l! and 3| corresponding in shape and size with the intermediate jaw plates 28--29 are fixed to the exterior sides of the yokes 24-25 for aligned registry therewith. The jaw plates 28-29-30-3I are each provided with a pair of spaced apertures 32-33 that are disposed in axial registry for receiving rivets 34 and 35 therethrough, the heads of the rivets 34-35 being deformed against the exterior jaw plates 3|l-3l to retain the upper jaw section in assembled relation and still afford the replacement of the jaw plates 28-29, 3-3l depending upon the dictates of commercial practice. Since the plates 28--3l are each formed symmetrical about a central plane normal to the plane of the plate, they may be placed in the jaws either way around and if damaged may be removed and reversed for further use.

Each of the jaw plates 28-29-3Il-3I have substantially V-shaped serrated jaw engaging surfaces 36 and 31 that permit the effective engagement of a cylindrical member such as a pipe 38. It is worthy of note that the upper jaw yokes 24-25 are riveted together intermediate the ends thereof as at 39 to preclude distortion thereof responsive to the application of force in engaging the pipe or other article 38 as will appear more fully hereinafter. The riveted joinder 39 together with the riveted detachable action of the upper jaw plates 28-29-30-3I to the yoke plates 25, render such a self-contained unit or element having aligned apertures 4|) proximate to the lower end for rotary support on a pivot 4| that projects therethrough and the spaced extensions 2li-2| of the handle Shanks |2-|3.

To this end, the pivot 4I (Figure 4) has a slot 42 extending longitudinally thereof to receive one extremity 43 of a spiral spring 44 which is mounted in confronting recessed portions 45--45 provided on the interior surfaces of the adjacently disposed and contacting yoke plates 24-25 in concentric relation with the pivot apertures 148. The other extremity 41 of the spiral spring 44 is oifset for engagement with an aperture 48 provided in the yoke plate 24, thereby imparting a clockwise urge on the yoke plates 24-25 to normally maintain the upper jaws 28-29- 30-3l in spaced relation with lower jaw plates 49-50.

The lower jaw plates 49-50 are elongated in configuration and are stamped to provide individually recessed sides 5| and 52 to serve as complements of the handle shank extensions 2li-2| for fitted engagement with the straight upper edges 22-23 thereof so as to serve as a shoulder support thereof in the direction of the longitudinal axis of the handle ID-II and its shank |2-l3 (Figure 1). The jaw plates 49-50 are stamped from suitable sheet material and their upper extremities take the shape of arcuate serrated engaging surfaces 53-54 which confront the V-shaped upper jaw surfaces 36-31 provided on each of the jaw plates 28-29- SEI- 3L The lower jaw plates 49-50 are maintained in spaced relation for mounting on the pivot 4| by means of a rivet 55 that extends therebetween proximate to the upper serrated jaw engaging surfaces 53 and 54, there being a spacer collar 56 provided therebetween for mounting on a rivet 55 to maintain the lower detachable plates 4.9-5!) in true spaced relation. The lower extremities of the jaw plates All-5D are also provided with a rivet 51 for engagement with the upper portion of the handle shanks |2-I3, thereby securely maintaining the lower jaw plates 4.9-50 in assembled and fixed relationship to effectively cooperate with the confronting top jaw plates 28-29-30-3I to effectively engage any member therebetween such as a pipe 38.

The lower jaw plates 49-50 are suitably hardened to impart thereto long lasting wearing qualities. The upper jaw plates 28-29 and 3-3I as well as the lower jaw plates 49-50 are readily replaceable by merely deforming the rivets 34, 35, 55, and 5l by the usual punching operation that permits their substitution and replacement of both the upper and lower jaw plates should such become worn or defective in the use thereof. It will be apparent that all of the component elements comprising a wrench of the type described herein, are prepared from stamping operations to the end of minimizing the cost of production and providing parts that can be hardened to meet the requirements and their functions.

For instance, the upper jaw plates 28-20, and Bil-3| as well as the lower jaw plates 49-50 will be hardened to a point of rendering the serrated surfaces 36-37 and 54 thereof effective as gripping edges without impairment thereto. This calls for an extremely hard and brittle characteristics while the upper jaw yoke plates 24-25 could not be heat treated in the same manner, since any brittle characteristic therein would preclude the functioning thereof to maintain the load between the gripping surfaces 36-3'! and 54. Consequently, the hardening treatment imparted tothe upper jaw yoke plates 24-25 would be definitely different from the treatment to which the jaw plates 28-29-30-3l and 49-50 are subjected to. This variation in heat treatment as well as the character of the steel alloy employed will vary throughout the wrench structure besides the handle portions Ill-I with their shanks |2-I3, and the seamless handle grip I4 which is pressed thereover. Individual and most advantageous heat treatment can, therefore, be imparted to the elements comprising the assembled wrench structure described herein.

In order to enable the spiral spring 44 to possess the desired tension, the pivot 4I is formed with a polygonal shoulder 59 which cooperates with a correspondingly shaped recess 6l) formed in the handle shank extension 2| in concentric relation with the pivoted shoulder provided therethrough. Consequently, the pivot 4| can be rotated to provide the desired tension in the spiral spring 44 and position so that its polygonal shoulder 59 is in registry with the corresponding recess or aperture formed in the handle shank extension 2| to maintain such against turning.

This adjustment in the spring tension is ef fected just prior to securing the parts in their assembled relation. Thereafter, the rivet heads are formed to preclude removal of the parts and to maintain the operations in the spring M in accordance with the tension imparted thereto. It will be apparent, therefore, from the foregoing description that a Very simple, inexpensive, and improved wrench structure has been provided which can be produced from stampings and afford individual heat treatment as well as the selection of a steel alloy for each particular part o1' parts depending upon their function and the desired operating characteristics thereof. It should be appreciated that the shape of the jaws 28-29, Sil-3| and 49-56 may be varied depending upon the use to which the wrench is designed andthe number of jaws may be varied depending upon the dictates of commercial practice.

Various changes may be made in the embodiv ment of the invention herein specifically described without departing from the invention or sacrificing any of the advantages or features thereof, an-d nothing herein shall be construed as limitations upon the invention, its concept or structural embodiment as to the whole or any part thereof except as defined in the appended claims.

I claim:

l. A wrench comprising, in combination: a handle formed of complemental, facing shells offset at one end from the plane of their meeting faces; a pair of jaw plates each formed with a shoulder seated on the ends of the respective offset portions; and vwith portions lapping with said offset portions; securing means passing through said shells and lapping portions; other securing means connecting the spaced. end of said jaws; a swinging jaw member pivoted between said offset handle portions; said swinging jaw comprising complemental plate portions having engaging faces at the pivoted end thereof and offset spaced portions at the free ends thereof; and a plurality of like jaw plates, at least one thereof between the last named offset, spaced portions, and at least one thereof placed exteriorly of each spaced portion and secured thereto by fastening means penetrating the end of the assembled swinging jaw.

2. A wrench comprising, in combination: a handle formed withspaced apart, jaw-carrying extremities; a swinging jaw member pivoted between said extremities; said member formed of complemental plates internally concave at the pivot portion of the assembly, and formed with spaced portions at the free end thereof; jaw plates secured between said spaced portions; and a spring housed in the space between said concave plates, anchored to the pivot and to said swinging jaw assembly and stressed to urge said swinging jaw assembly toward normal position of rest.

3. A pipe jaw comprising, in combination: a pair of complemental, substantially arcuate members secured in meeting engagement at a portion of their extent and formed with offset spaced portions for the remainder of their extent; a plurality of like jaw plates, each shaped as halves symmetrical about a central plane nor- `mal to the plane of the plate with a serrated work engaging edge surface on each half at an obtuse angle to each other; whereby said plates are reservible for use; at least one of said plates between and at least one on the outside of and detachably secured to said offset portions.

RALPH E. LILLEBERG. 

